rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (12 ticks this GP) idle=2bec/1/0x4000000000000000 softirq=764/766 fqs=146 rcu: (detected by 0, t=10002 jiffies, g=1053, q=2041 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 624 Comm: syz.3.90 Not tainted syzkaller #0 0043dfd2fbaf315da186ee57f2b2b1c8bfff300f Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:-1 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x26c/0x2a0 mm/kasan/generic.c:189 Code: eb 28 4f 8d 5c 33 01 eb 21 4f 8d 5c 33 02 eb 1a 4f 8d 5c 33 03 eb 13 4f 8d 5c 33 04 eb 0c 4f 8d 5c 33 05 eb 05 4f 8d 5c 33 06 <4d> 89 dd 4d 85 db 0f 84 51 ff ff ff 4d 01 d1 4d 39 cd 75 11 41 83 RSP: 0018:ffffc9000dc5fbf8 EFLAGS: 00000002 RAX: f300f204f1f1f101 RBX: ffffffffffffffff RCX: ffffffff858dcbf2 RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff889e9040 RBP: ffffc9000dc5fc20 R08: ffffffff889e9043 R09: 1ffffffff113d208 R10: dffffc0000000000 R11: fffffbfff113d208 R12: dffffc0000000000 R13: 0000000000000001 R14: fffffbfff113d209 R15: 1ffffffff113d208 FS: 000055557bd68500(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8a396e7d60 CR3: 0000000113f3a000 CR4: 00000000003526b0 Call Trace: __kasan_check_write+0x18/0x20 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline] queued_spin_lock include/asm-generic/qspinlock.h:111 [inline] do_raw_spin_lock include/linux/spinlock.h:187 [inline] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0xa2/0x150 kernel/locking/spinlock.c:162 vga_put drivers/pci/vgaarb.c:547 [inline] vga_arb_release+0x20f/0x950 drivers/pci/vgaarb.c:1455 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e3/0x250 kernel/task_work.c:240 resume_user_mode_work+0x36/0x50 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x64/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f8a3898ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff1e26cee8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000008e2e RCX: 00007f8a3898ebe9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f8a38bb7da0 R08: 0000000000000001 R09: 0000000e1e26d1df R10: 0000001b2df20000 R11: 0000000000000246 R12: 00007f8a38bb5fac R13: 00007f8a38bb5fa0 R14: ffffffffffffffff R15: 00007fff1e26d000 rcu: rcu_preempt kthread starved for 9709 jiffies! g1053 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:0 pid:18 tgid:18 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_timeout+0x139/0x3a0 kernel/time/timer.c:2619 rcu_gp_fqs_loop+0x2f2/0x12f0 kernel/rcu/tree.c:2053 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:2255 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244